fitk3 - tpcclib 0.8.0 © 2023 by Turku PET Centre
Non-linear fitting of two-tissue compartment model to plasma input, blood,
and tissue time-activity curves (PTAC, BTAC, and TTAC) to estimate
parameters K1, k2, k3, and Vb. Sample times must be in minutes.
| | K1 | k3 |
| | --> | -------> |
| Ca | <-- | C1 <------- C2 |
| | k2 | k4=0 |
Usage: fitk3 [Options] ptacfile btacfile ttacfile endtime resultfile
Specify the constraints for model parameters;
This file with default values can be created by giving this
option as the only command-line argument to this program.
Without filename the default values are printed on screen.
Standard deviations are calculated and saved in results (y),
or not calculated (N, default).
Program runs a lot faster if SD and CL are not calculated.
95% Confidence limits are calculated and saved in results (y), or
not calculated (N, default).
Enter a fixed Vb; fitted by default.
-r=<Reference region id or filename>
Optional reference region is used to constrain K1/k2 in other regions;
Also k3 is fitted to reference region data, thus any large region
(for example cortex) can be used here.
Fitted regional TACs are written in DFT format.
Fitted and measured TACs are plotted in specified SVG file.
Display usage information on standard output and exit.
Display version and compile information on standard output and exit.
-d[n], --debug[=n], --verbose[=n]
Set the level (n) of debugging messages and listings.
Suppress displaying normal results on standard output.
Suppress displaying anything except errors.
Example 1: estimate K1, K1/k2, k3 and Vb
fitk3 ua919ap.bld ua919ab.bld ua919.tac 60 ua919k3.res
Example 2: estimate K1 and k3; Vb is constrained to 4.5% and K1/k2 is
constrained to K1/k2 estimated from region 'occip'
fitk3 -Vb=4.5 -r=occip ua919ap.bld ua919ab.bld ua919.tac 60 ua919.res
See also: patlak, lhsol, p2t_v3c, tacweigh, taccbv, rescoll
Keywords: TAC, modelling, irreversible uptake, k3, Ki, 2TCM